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21.
Chick embryo fibroblasts transformed by Rous sarcoma virus have an increased content of two membrane proteins of molecular weights 78,000 and 95,000. The increased content of the 95,000-dalton protein and the principal increase in the content of the 78,000-dalton protein are not an early consequence of cell transformation but instead are secondary to the rapid depletion of glucose from the growth medium of transformed cells. When glucose is maintained at high levels in the growth medium of transformed cells, the synthesis of the 95,000-dalton protein is arrested and that of the 78,000-dalton protein is markedly suppressed. Upon removal of glucose from the growth medium of normal cells, these proteins increase to levels comparable to those of transformed cells. Because the amount of these two proteins is influenced by the presence or absence of glucose, we suggest they be referred to as "glucose-regulated proteins." GRP-78 and GRP-95. These proteins may have an important role in regulating the utilization of glucose in cultured cells.  相似文献   
22.
In recent years, cognitive-behavioural models of OCD have increasingly recognized the potential role of feared possible selves in the development and maintenance of OCD, while simultaneously re-examining factors that have historically been linked to self-perceptions in OCD. The current article describes the development and validation of a multidimensional version of the Fear of Self Questionnaire (FSQ-EV) in a non-clinical (N = 626) and clinical OCD sample (N = 79). Principal component analyses in the non-clinical sample revealed three conceptually and factorially distinct components revolving around a feared corrupted possible self, a feared culpable possible self and a feared malformed possible self. The questionnaire showed a strong internal inconsistency, and good divergent and convergent validity, including strong relationships to obsessional symptoms. In particular, the corrupted feared self predicted OCD symptoms independently from depression and other related self-constructs and obsessive beliefs, while also strongly interacting with importance and control of thoughts in the prediction of almost all specific symptoms of OCD. Results are consistent with the notion that self-constructs can be conceptually and empirically distinguished from obsessive beliefs and appraisals with significant potential to improve our understanding of OCD and related disorders.  相似文献   
23.
ObjectivesTo test the reliability of Lateral cephalometric radiographs (LCRs) for use in the assessment of the upper airway, hyoid bone, soft palate, and tongue.Materials and MethodsThe records of 57 healthy Chinese children from a nonhospital population (mean age = 12.6 years, SD = 0.5, 28 males and 29 females) who received two consecutive LCRs in the natural head posture were retrospectively analyzed. Fifteen linear, angular, and area measurements were used to describe the airway, hyoid bone, soft palate, and tongue. The reliability between the two LCRs was assessed with the intraclass correlation coefficient (ICC) and F-test. Errors were estimated with the Dahlberg and Bland-Altman method, and intra- and inter-assessor agreements were determined.ResultsMeasurements of upper airway and hyoid bone had excellent method reliability, intra-assessor reliability, and inter-assessor reliability (ICC > 0.8). However, the method reliability and the inter-assessor reliability for soft palate and tongue was less favorable (ICC from 0.60 to 0.96). Soft palate area and thickness were the most critical parameters. Intra-assessor reliability was greater than both method reliability and inter-assessor reliability (which were similar).ConclusionsThe measurement of upper airway morphology, defined as the intramural space, and of the hyoid bone position were highly reliable on LCRs of children. However, the limited reliability in the assessment of tongue and soft palate area may compromise the diagnostic application of LCRs to these structures.  相似文献   
24.
25.
Shortage of deceased donors is a severe problem in recent years in China especially in a culture in which brain death criteria is not widely accepted. Donation after cardiac death (DCD) has been reported to expand the donor pool despite higher rates of primary nonfunction (PNF) and delayed graft function (DGF) after transplantation. We collected 71 DCD kidney transplants performed at our hospital between February, 2007 and June, 2012 with aims to demonstrate the feasibility of DCD donation in China. All patients were followed up, and postoperative complications and graft loss were recorded. The PNF rate was 2.8%, and DGF rate was 28.2%. The 1‐ and 3‐year graft survival was 95.7% and 92.4%. In conclusion, graft survival of DCD kidney transplantation in China is excellent despite of higher rates of PNF and DGF after transplantation.  相似文献   
26.
Using TiOiPr4 with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOiPr4 only. At 60 °C, TiOiPr4 with furPz exhibited a higher catalytic activity (approximately 3-fold) than TiOiPr4. At room temperature, TiOiPr4 with BuPz exhibited a higher catalytic activity (approximately 17-fold) than TiOiPr4. High molecular mass PLA (MnGPC = 51 100, and Đ = 1.10) could be produced by using TiOiPr4 with furPz in melt polymerization ([TiOiPr4] : [furPz] = 1000 : 1 : 1 at 100 °C, 240 min). The crystal structure of MePz2Ti2OiPr7 revealed the cooperative activation between two Ti atoms during LA polymerization.

Using TiOiPr4 with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOiPr4 only.  相似文献   
27.
Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus, causing severe central nerve system diseases without specific treatments. The NS2B-NS3 protease of flaviviruses mediates several cleavages on the flavivirus polyprotein, being believed to be a target for antiviral therapy. NS2B is the cofactor of the viral serine protease, correlating with stabilization and substrate recognition of the NS3 protease. In this study, we investigate the functional determinants in the JEV NS2B for the activation of the NS3 protease. Cis- and trans-cleavage assays of the deletions at the N-terminal of NS2B demonstrated that the NS2B residues Ser(46) to Ile(60) were the essential region required for both cis and trans activity of the NS3 protease. In addition, alanine substitution at the residues Trp53, Glu55, and Arg56 in NS2B significantly reduced the cis- and trans-cleavage activities of the NS3 protease. Sequence alignment and modeled structures suggested that functional determinants at the JEV NS2B residues Ser46 to Ile60, particularly in Trp53, Glu55 and Arg56 could play an important configuration required for the activity of the flavivirus NS3 protease. Our results might be useful for development of inhibitors that block the interaction between NS2B and NS3.  相似文献   
28.
OBJECTIVE: The interactions between non‐steroidal anti‐inflammatory drugs and Helicobacter pylori have not been sufficiently documented to date. The aim of this study was to investigate the possible effects of aspirin and indometacin on the growth of H. pylori and to determine the effects of aspirin on the susceptibility of H. pylori to some antimicrobials. METHODS: Kinetic studies were performed by inoculating strains of H. pylori in brucella broth with different concentrations of aspirin and indometacin. Growth of bacteria in the broth was assessed spectrophotometrically and by viable colony counts after incubation for 24 and 48 h. Bacterial morphology was determined by Gram stain under light microscopy. The minimal inhibitory concentration (MIC) of aspirin and indometacin was determined by the standard agar dilution method. The MIC of amoxicillin, clarithromycin and metronidazole was measured in the presence and absence of aspirin by the E‐test method. RESULTS: Kinetic studies revealed that aspirin and indometacin inhibited the growth of H. pylori in a dose‐dependent manner. The bactericidal activity of these agents was expressed by cell lysis. Aspirin at 400 µg/mL produced an almost 2‐log decrease in the number of CFU/mL at 48 h. Similar inhibitory effects were obtained when 100 µg/mL indometacin was tested. The MIC at which 90% of H. pylori was inhibited was 512 µg/mL and 128 µg/mL for aspirin and indometacin, respectively. Increased susceptibility of H. pylori to amoxicillin, clarithromycin and metro­nidazole was found in the presence of aspirin. CONCLUSIONS: Aspirin and indometacin could significantly inhibit the growth of H. pylori when incubated in brucella broth in vitro. A subinhibitory concentration of aspirin enhanced the susceptibility of H. pylori to some antimicrobial agents.  相似文献   
29.
Coronary spasm in acute myocardial infarction   总被引:1,自引:0,他引:1       下载免费PDF全文
A 30 year old man had an acute anterolateral myocardial infarction following which he developed unstable angina requiring percutaneous transluminal coronary angioplasty. He subsequently developed further angina with recurrence of coronary artery lesions that were reversed by intracoronary nitrate. A diagnosis of prinzmetal (vasospastic) angina was made and this had been the apparent cause of his myocardial infarction. He was treated with a calcium antagonist and an oral long acting nitrate with resolution of symptoms. He remained well and symptom free, and was reviewed in the outpatient clinic six weeks after discharge without problems.

Keywords: coronary spasm; acute myocardial infarction; syndrome X; prinzmetal's angina  相似文献   
30.
Asians and Pacific Islanders (API) are among the fastest growing minority groups within the USA, and this growth has been accompanied by an increase in HIV incidence. Between 2000 and 2010, the API HIV infection rate increased from 4.5% to 8.7%; however, there is a paucity of HIV-related research for this group, and even less is known about the prevalence and correlates of antiretroviral therapy adherence behavior, quality of life, impact of stress, and efficacious self-management among HIV+ API Americans. This paper examines how acculturation and perceived stress affect depression symptomatology and treatment seeking in the HIV+ API population. A series of cross-sectional audio computer-assisted self-interviews were conducted with a convenience sample of 50 HIV+ API (29 in San Francisco and 21 in New York City). The relationship between acculturation and perceived stress was analyzed, and the results indicate that for those HIV+ API who reported low or moderate acculturation (as compared to those who reported high acculturation), stress was significantly mediated by depression symptomology. Interventions to address acculturation and reduce perceived stress among API generally and Asians specifically are therefore needed.  相似文献   
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